Developers guide

Chapter 6: Power Management
Events
38 Psion Teklogix Mobile Devices SDK Developers Guide
6.1.2 Events
The following power state events are generated by the computer and can be detected by the
Mobile Devices SDK:
•AC Power online
• AC Power offline
• Battery status change
• Power information change
• Power transition
6.1.3 Power-on Keyguard
The power-on keyguard feature specifies the number of key presses that are needed to power up
the Psion Teklogix computer. Multiple key presses protect the hand-held computer from acciden-
tal power-up.
This option is only available on the WORKABOUT PRO with the Windows Mobile operating
system. The Power-on Keyguard variable can be set to one of two values as follows:
• OneKey — User must press and hold the [ENTER] key for two seconds.
• TwoKey — User must press and release the [BLUE] key, then hold the [ENTER] key for two
seconds.
6.1.4 Reset Key
On each Psion Teklogix computer there are default key combinations which can be used to reset
power. The combinations can be enabled or disabled via the Mobile Devices SDK. The following
options are available:
• BoostResetKey — Enable/disable boot to BooSt (bootstrap menu) reset key sequence. If disa-
bled, the device will do a cold reset instead when the BooSt reset key sequence is performed.
• ColdResetKey — Enable/disable cold reset key sequence.
On devices running Windows Mobile, this option is invalid; use WarmResetKey instead.
• WarmResetKey — Enable/disable warm reset key sequence. If disabled, the device will do
nothing if the warm reset key sequence is performed.
6.1.5 Battery Information
6.1.5.1 Battery Threshold
Some Psion Teklogix computers have only a small backup battery, or no backup battery. On these
computers, once the main battery has completely discharged, users have a very short time during
which to change the battery before all volatile data is lost. In this situation, it can be desirable to
have the device give the low battery warning prematurely, thus ensuring it gets replaced or
recharged before data is lost.
Setting the battery suspend threshold forces the computer to suspend when that threshold is
reached, before the main battery has fully discharged. The battery suspend threshold value is
expressed as a percentage of battery charge remaining. The set method will accept any integer
value from 0 to 20, however the actual range accepted by a given computer model may not actu-
ally go as high as 20; any value set above the terminal’s maximum value will be stored as the
maximum (e.g. setting a value of 18 on the NEO will result in a value of 13 being stored).